The present invention relates to a flat panel display control apparatus and more particularly to an apparatus controlling a flat panel display device which is compatible with a cathode-ray tube (referred to as a CRT hereinafter) display device.
Conventionally, CRT display devices are the most popular as display devices for personal computers. CRT display devices are superior to other display devices in terms of luminance, contrast and the like. However, since CRT display devices are heavy and large in size, they can not be applied to handheld personal computers. Meanwhile, in addition to the CRT display device, flat panel display devices such as a liquid crystal display device (referred to as an LCD hereafter), a plasma display device, an electro luminescent (EL) display device and the like are available. Although they were at first used for relatively compact devices, such as wrist watches, electronic calculators and the like, they can display the same number of dots as the CRT display device in keeping with the trend to enlarged display sizes in recent years. Thus, flat panel display devices are now used for handheld personal computers in place of CRT display devices.
However, in the computer field, it is important to provide software compatibility when a new equipment is developed. When a newly developed computer does not have software compatibility with respect to a conventional computer, new software must be developed. In order to avoid such a need, newly developed computers are generally designed so that conventional computer software can be used.
In the context, the case of a newly developed personal computer with a flat panel desplay device having software compatibility with a conventional personal computer with a CRT display device will be considered. Display for emphasizing display by color is performed by the CRT display device. The flat panel display device can display in only a single color and has no gradation as emphasized display. Accordingly, the video signal of the flat panel display ORs R G B signal generated for CRT display device or ignores the attribute of color set. In these methods, when the color setting is made on both foreground and background, the above distinction becomes impossible to be performed. Furthermore, when the attribute is ignored, these methods contains the defect of incapability of blink or inversion. Therefore, even if a personal computer with a flat panel display device having software compatibility with a personal computer with a CRT display device were to be developed, such compatibility could not provide color display as an emphasized display. Since the current personal computer with a CRT display device frequently utilizes color display, if such display can not be used in a personal computer with a flat panel display device, the corresponding portion would not be displayed resulting in inconvenience and thereby impairing practical use.